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Claim. Theorem 1 of G. Melfi, On the conditional infiniteness of primitive weird numbers (p. 509; Melfi 2015): let k≥1k\ge1 and let aa, bb be positive odd integers such that p=2k+2−ap=2^{k+2}-a and q=2k+2+bq=2^{k+2}+b are prime. If b+3<a<2(k−1)/2b+3<a<2^{(k-1)/2}, then n=2kpqn=2^kpq is a primitive weird number. The paper deduces (pp. 509--510) that if pn+1−pn<0.1 pn1/2p_{n+1}-p_n<0.1\,p_n^{1/2} for all sufficiently large nn, where pnp_n is the nnth prime, then there are infinitely many primitive weird numbers, all of the form 2kpq2^kpq. Under that hypothesis this answers the second question of Problem 470 yes. The first question, on odd weird numbers, is not answered: the paper remarks only (Section 4) that the proof of Theorem 1 extends with 2k2^k replaced by an almost perfect number mm, one with σ(m)=2m−1\sigma(m)=2m-1, so that an odd almost perfect number greater than 11 would give an odd weird number. The paper takes weird to mean σ(n)>2n\sigma(n)>2n and not a sum of distinct proper divisors of nn, the reading recorded under the problem page's Formulation.

Hypothesis. The prime-gap bound pn+1−pn<0.1 pn1/2p_{n+1}-p_n<0.1\,p_n^{1/2} for all large nn is unproved. Cramér's conjecture pn+1−pn=O((log⁡pn)2)p_{n+1}-p_n=O((\log p_n)^2) would give it, and so would the much weaker conjecture, which the paper attributes to Gonek, that pn+1−pn<pnεp_{n+1}-p_n<p_n^{\varepsilon} for every ε>0\varepsilon>0 and all large nn. The unconditional bound pn+1−pn<pn0.525p_{n+1}-p_n<p_n^{0.525} of Baker, Harman and Pintz, which the paper calls very close to what is needed, is not enough. The claim gives no unconditional answer.

Depends on. Nothing in this wiki; the hypothesis is stated above.

Acceptance. Published in J. Number Theory 147 (2015), 508--514, a refereed journal, DOI 10.1016/j.jnt.2014.07.024 (refereed); the article was available online on 16 September 2014, which dates this page. No arXiv posting is recorded. The site credits the conditional result in its commentary but labels the problem OPEN, so that credit is not acceptance and no reviewed evidence is listed.